Hi...
There can be lots of reasons about you problem.But i am sure that it is not cause of ram cause i played this game in 32 mb ram once and it worked fast i have 64 ram right now and also fast..
The exact solution is a little bit long but it will work.backup your saves and uninstall it.Then reinstall again.Also do not forget that if you ve full installation it will load muc much much faster.These will work but if not i am unhapply saying that try to decrease some sound graphic effects..
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Wy WorDs WilL Speak ThE
TrUtH, my StreNgtH WilL aid The WeaKen OneS, And mY WisDom Show The Light....